The Declaration Impact

The Declaration of Independence has played a big role in our government since the day it was passed on July 4, 1776. You can see examples
of this in day to day life. Even though Thomas Jefferson had slaves at the time he wanted everyone to be treated equal. "We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain inalienable rights, that among these are life, liberty, and the pursuit of happiness". What impact did the Declaratrion of Independence have on our Country? If you could, would you change anything? If so, what?